Originally Posted by flyems
iPad battery failure, or atomic powered Heart Pace-Maker
I'd be interested in data, specifically the means of getting fission from Pu-238, and the burn rate expected from a battery to produce this sort of effect?
Some hundreds or a few thousands of Pu-238 powered pacemakers were made and implanted in patients a few decades ago. As with the RTGs on deep space probes, this is a different isotope of Plutonium than that of interest for bombs. The mechanism is natural spontaneous decay, so no "means of getting fission" is employed at all--it would decay just sitting on the shelf. The amount of Pu-238 was in the range of 2 to 4 Curies. By the definition of a Curie, that means the radioactive decay events per second were in the range of 70 to 150 billion. As Pu-238 has an 88 year half life, and these devices were manufactured a while ago, the current rate would be less.
For most of us watts are more natural units than curies or disintegrations, so perhaps it may help to say that at time of manufacture the thermal decay heat was about a tenth of a watt (obviously electric power generation was rather less).
Pu-238 is not the stuff you want to make bombs of, and is actually regarded as a contaminant by bomb makers.
A speculation that the Mogadishu event could have been pacemaker caused is ill-informed and foolish. None of the battery types used have potential for so energetic an event. Especially not the atomic-powered ones.